Page layout
Headings
To divide your page's content, and add block titles, you can add h2 tags.
application/blog/admin.xml
<page for="blogitem">
<title>
<singular>Item</singular>
<plural>Items</plural>
</title>
<content>
<h2>Item content</h2>
<input for="title">
<title>Item title</title>
</input>
<input for="content">
<title>Item content</title>
</input>
<h2>Comments</h2>
<list for="comment">
<column for="date"/>
<column for="author"/>
</list>
</content>
</page>
Grid
It's possible to use grid tags to create custom layouts for admin pages. These tags require a size attribute, which takes a fraction as value.
application/blog/admin.xml
<page section="blog">
<title>Blog</title>
<content>
<grid size="1/2">
<p>These columns are equal width</p>
</grid>
<grid size="1/2">
<p>These columns are equal width</p>
</grid>
<grid size="1/3">
<p>This column is smaller</p>
</grid>
<grid size="2/3">
<p>This column is larger</p>
</grid>
</content>
</page>
Tabs
If your page contains a lot of content, it might be preferable to organise related inputs into separate tabs. This can be achieved by adding tab tags alongside (or instead of) a page's content tag.
application/blog/admin.xml
<page for="blogitem">
<title>
<singular>Item</singular>
<plural>Items</plural>
</title>
<tab>
<title>Item content</title>
<content>
<input for="title">
<title>Item title</title>
</input>
<input for="content">
<title>Item content</title>
</input>
</content>
</tab>
<tab>
<title>Comments</title>
<content>
<list for="comment">
<column for="date"/>
<column for="author"/>
</list>
</content>
</tab>
</page>